Field of the Invention
The present invention relates to an information processing apparatus that is capable of supplying power to an external device, a printing apparatus, a method of controlling the information processing apparatus, a method of controlling the printing apparatus, and a storage medium.
Description of the Related Art
Conventionally, as an interface for supplying power from an image processing apparatus to an external peripheral device, a USB (Universal Serial Interface) interface using USB cable connection using a Vbus power line (hereinafter simply referred to as “Vbus”) has come into widespread use.
The USB standard specifies power which can be supplied to one peripheral device as a rated voltage of 5 V, a maximum current of 500 mA, and a power consumption of 2.5 W (USB 2.0), or a rated voltage of 5 V, a maximum current of 900 mA, and a power consumption of 4.5 W (USB 3.0).
In recent years, the USB standard is extended, and the USB PD (USB Power Delivery) standard that specifies power which can be supplied up to a maximum power consumption of 100 W is designed. The USB PD standard specifies a negotiation method for notifying a peripheral device of suppliable power or specifying power to be supplied, by communication with the peripheral device via the Vbus.
An easiest method for supplying power from an image processing apparatus to a peripheral device in a manner conformant to the USB PD standard is to increase a power supply capacity of the image processing apparatus to thereby ensure a capacity sufficient to achieve both image processing and power supply.
If this method is employed, power of 100 W at maximum per one peripheral device is supplied according to the USB PD standard. Therefore, a simple increase in the power supply capacity of the image processing apparatus results in a significant increase in the costs of the image processing apparatus and an increase in the whole size of the same.
To prevent increases in the costs and size, it is necessary to achieve not only image processing but also power supply to a peripheral device, with a limited power supply capacity. To this end, when supplying power from an image processing apparatus to a peripheral device, there has been proposed a technique of limiting the number of recording elements for image processing to thereby ensure power to be supplied to the peripheral device (see e.g. Japanese Patent Laid-Open Publication No. 2005-74945).
However, the technique disclosed in Japanese Patent Laid-Open Publication No. 2005-74945 is a technique that is effective for an inkjet image processing apparatus, and in a case where a plurality of recording elements are not used for recording, such as an electrophotographic image processing apparatus, it is impossible to ensure the power to be supplied by limiting the number of recording elements.
Further, power which can be supplied by an image processing apparatus largely changes depending on conditions of the image processing apparatus, such as a standby state, operating states including printing and scanning, and error states including a paper-out condition and a toner-out condition.
As described above, suppliable power from the image processing apparatus is not uniform depending on the states thereof, and hence there is a problem that suppliable power compliant with the USB PD standard cannot be unconditionally notified.